You know the scenario. You enter a room thick with smog from a fog machine. Your only source of light is a strobe. Everything looks like it’s in stop motion.

A bulky man ahead of you — you can’t make out any of his features, just that he’s coming toward you — he lifts a detoothed chainsaw above his head and lets it growl. Nothing to fear, you tell yourself. It’s detoothed.

But what if it isn’t?

Now you feel a scream forming in your chest.

The stop-motion feel created by a strobe light can really enhance the mood of a haunted house. But what kind of effect does it have on the eyes?

Not much, actually.

Although two issues may arise.

Two Ways Strobe Lights Can Take a Toll

Rumors that strobe lights cause astigmatism are nothing more than that: rumors. But strobe lights can cause eye fatigue or, if the strobe light is powerful enough, a corneal surface burn.

Eye fatigue

Strobe lights can cause eye fatigue, because they distort the way the brain perceives motion.

Think of it like a movie. A movie consists of frames, hundreds of thousands of them, moving in quick succession (24 frames per second). The mind can’t take in each frame individually, so it perceives all the frames together as being in motion.

A strobe light, however, flashes light at a much slower rate. So it tricks the mind into seeing the world as “individual frames.”

While this trickery isn’t necessarily bad for the eyes, it can cause you to focus more intensely, which can strain your eyes.

If you’re experiencing eye fatigue, your eyes might:

Ache

Feel dry

Have difficulty focusing

Be sensitive to light

But eye fatigue, other than being an annoyance, is rarely a serious condition. If you experience it, close your eyes for a few minutes. You might consider covering them with your palms.

Corneal Surface Burn

Corneal surface burn is more serious than eye fatigue. If the strobe light is more than 150 watts, the amount of lumens it puts out may be enough to damage your eye if you stare at it directly for a long period.

Corneal surface burn is like a sunburn on the surface of the eye. When light is too strong or lasts for too long, it heats the colored part of the eye. That part of the eye absorbs the light — that’s why you see a bright spot when you look away — and the eye radiates the heat, which can burn it.

Usually, corneal surface burn heals, but it might take a few days.

Of course, it’s highly unlikely you’ll stare at the strobe lights directly, much less long enough to cause damage, what with being shuffled through a haunted house.

Regardless, a basic rule of thumb is this:

If the strobe light hurts your eyes, don’t stare at it.

This Halloween, don’t let strobe lights scare you away from some haunted house fun. Just make sure your eyes feel comfortable. After all, some things you can’t unsee.